Boiler-furnace



J. H. STANNARD, SR.

BOILER FURNACE. APPLICATION FILED OCT. 7, 1919.

Patented Nov. 1, 1921.

UNITED STATES PATENT OFFICE.

JOSEPH H. STANNARD, SR., OF COLUMBIA, SOUTH CAROLINA.

BOILER-FURNACE.

Application filed October 7, 1919.

To all whom it may concern,

Be it known that'I', JOSEPH H.7STANNARD, Sr. a citizen of the United States, residing at Columbia, in the county of Richland and StateofSouth Carolina, have invented new and useful Improvements in Boiler-Furnaces, of which the following is a specification.

The present invention relates to improvements inboiler furnaces andmore especially to the fire box of such a boiler.

The particular object of the invention is to provide within the fire box of a steam boiler anarch which will act to properly direct the products of combustion along the crown sheet and uniformly distribute them to all of the boiler fi ues.

A further object of the invention is to provide means. whereby a maximum sized grate may beemployed' and all partsthereof utilized.

With the constructions heretofore proposed it has been'impossibleto use a grate extending continuously from the rear flue sheet of the boiler to the rear end of the fire box and have the products of combustion uniformly distributed to all of the flues,

While the invention may be advantageously employed with any horizontal steam boiler it is particularly adapted for locomotive boilers and'is therefore illustrated in the accompanying drawings inconnection with such a boiler.

In the drawingsFigure 1, is a vertical sectional view through a locomotive boiler having one embodiment of the present invention applied thereto.

Figs. 2 and 3 aresectional views of the fire box, showing slightly modified forms of the invention.

Referring to the drawings, 1 designates the water space or chamber of the boiler through which extend the usual flues 2, the ends of which are supported in front and rear flue sheets 3,4; The rear flue sheet is extended downward below the body of the boiler 1, to provide part of a water leg 5, and at its rear end the body of the boiler is caused to extend across the rear end of the fire box, admission to which is through apertures 6, 7, that are closed by suitable doors not illustrated.

The parts of the boiler before referred to m y be f y suitable constru ion, h

' vSpecification of Letters Patent.

Patented Nov. 1, 1921.

Serial No. 329,150.

particular form conventionally illustrated being what may be considered a standard type.

Tubes 8 connect the water leg 5 with the water chamber at the rear'end of the fire box, such tubes being inclined upwardly from their forward to their rear ends. It is customary to. support on such tubes an arch of refractory material which extends from one side wall of the fire box to the other end generally parallel to the tubes 8. Practical experience with such a construction shows that as the draft through the lower tiers of tubes or flues is stronger than that through the upper series the products of combustion rising from the grate and passing over the rear end of said arch are caused to be drawn downwardly through the lower series of flues and the uppermost tubes receive little if any direct heat therefrom.

By the present invention the arch supported by the tubes 8, is provided with an upwardly projecting portion 9, the upper surface of which, as shown in Fig. 1, is flat or parallel. with the crown sheet of the fire box. Preferably said upward projecting portion is made of substantially triangular form in longitudinal section, the forward end thereof extending parallel with the rear flue sheet and being spaced therefrom sufficiently to afford room for a workman to inspect, and if necessary repair. the connection between such sheet and the boiler flues. The space between the top of the portion 9 of the arch and the crown sheet of the firebox is sufiicient to permit a workman to enter the combustion chamber immediately in rear of the flue sheet 4. As shown in Fig. 1, the arch referred to includes a portion 10, extending parallelwith the tubes 8, and which may, as shown, be separated slightly from the rear flue sheet to provide a passage 11, for flame rising from the grate or in some instances said section 10, may extend continuously to, said flue sheet.

'It has been practically demonstrated that with an arch of the form and relative proportions shown the products of combustion rising from the grate will be uniformly dis tributed to all of the tubes or flues and it will be seen that such structure provides for maintaining the products of combustion in contact with the crown sheet of the fire box throughout its length. This results in obtaining the maximum heating efliciency from the fire. In the embodiment of the invention illustrated in Fig. 2, the upwardly extending portion of the arch has the top surface of the forward portion 12 thereof, inclined downward slightly from the top of the rear portion 13, but the relation of the forward end thereof to the rear flue sheet is substantially the same as in Fig. 1.

Instead of making the arch of refractory material as before described and illustrated in Figs. 1 and 2 it may be formed as a part of the water chamber of the boiler. In this construction, which is shown in Fig. 3, the portion 14 of the water chamber is projected over the grate in the fire box and communicates with the body of the boiler through the side walls of the .fire box and also through an opening 15in the rear flue sheet. 'The top of such chamber 14, like the upper surface of the portion 9, of the arch shown in Fig. 1 causes the products of combustion to travel along the crown sheet throughout the length thereof and the wall 16 of the water chamber 14 is so related to the rear flue sheet that said products of combustion are uniformly distributed to all of the fines.

It will be understood that the distance separating the abutment or upward projection of the arch fromthe rear flue sheet will be accurately determined by the strength of the draft which is to be induced through the several lines prior to building the arch in the fire box. The amount of draft in the invention illustrated is controlled by an adjustable damper 17, arranged within the smoke box at the forward end of the boiler, a suitable perforated baffle-18 being provided in the rear portion of said box in front of the upper series of tubes or lines and a screen 20 being provided for preventing cinders and the like from escaping from the smoke box.

It will be seen that the present invention enables use to be made of a grate of maximum size as it can extend completely from the rear flue sheet 1, to the rear wall of the fire box and that the battle or means for controlling the passage of products of combustion to the fines does not obstruct or out off any portion of the grate surface. Further it is possible to admit flame to the combustion chamber between the upwardly extending portion of the arch and the rear flue sheet so as to insureperfect combustion of the gases therein and the products of combustlon are uniformly distributed over the entire rear face of the rear flue sheet and to all of the tubes opening therethrough.

Having thus described the invention what is claimed is: c

1. In a horizontal fire tube boiler, including a fire box provided with a grate, a crown sheet and a substantially vertical tube sheet, an arch extending from side to side of the fire box above the grate with its lower surface inclined longitudinally and its upper surface separated from the crown sheet by a passage of substantially;uniform height throughout the length of the arch and extending to within a short distance of the tube sheet, said arch being provided with means for preventing direct passage of products of combustion from most of the grate areato the tubes opening through the lower section of the tube sheet.

2. In a horizontal fire tube boiler, including a fire box provided with a grate, a crown sheet and a substantially vertical tube sheet, an arch extending across the fire box above the grate, throughout the greater portion of the length thereof and having, adjacent the tube sheet, an imperforate surface extending substantially parallel to and at a relatively slight distance from said tube sheet across the adjacent ends of the tubes in approximately. the lower half of-the boiler, whereby the products of combustion are caused to travel throughout the length of the arch in planes above the level of the lower half of the series of fire tubes; for the purpose described. Y

3. In a' horizontal fire tube boiler, including a fire box provided with a grate, a crown sheet and a substantially vertical tube sheet, an arch extending from side to side of the fire box and throughout the greater part of the length thereof, said arch including an upwardly projecting portion, substantiallytriangular in longitudinal section with its vertical portion extending to approximately above the level of the low r half of the series of fire tubes and spaced from and parallel to the tube sheet, for the purpose described.

In testimony, whereof I have hereunto set my hand in presence of two subscribing witnesses.

a JOSEPHI-I. STANNARD, sR. Witnesses:

DAVID E. PAOKER, FRANK R. T RNER. 

